Hiiragi is renowned as Japan's premier assassin, serving under the White King. At one point, he was dispatched to eliminate "Tatara." Additionally, Hiiragi trained Shuri, Asagi, and Shidou in combat techniques. The name "Hiiragi" signifies holly, and his targets often receive a holly warning, signaling their imminent demise at his hands.
The emperor entrusted Hiiragi with leading the invasion of Awaji Island. His mission entailed eliminating the current leader and returning Ginko to Kyoto. Despite successfully completing both tasks, Hiiragi has never forgiven himself for deeply wounding the White King. Consequently, he now serves her without question as a form of penance. Hiiragi is the sole individual who truly understands Ginko's feelings. Before her arranged marriage, it is suggested that he loved—and continues to love—her.
In time, Shuri and Nakijin manage to defeat him in battle, an encounter that costs him an arm. Ultimately, Asagi delivers the final blow, resulting in Hiiragi's demise alongside Ginko when the palace collapses upon itself.
